端承型基桩的桩-土作用机理研究探讨

针对端承型单桩的桩-土作用机理，提出了复杂介质中端承型单桩的地基-基础模型，将“广义弹性理论法”、“镜像法”、传递函数法、线性变形层理论和优化反分析方法相结合，给出了一种分析计算复杂地基中端承型单桩承载性能计算的理论方法。并针对桩尖嵌岩深度的不同情况进行了探讨，给出了嵌岩桩的理论模型和计算分析方法。利用该方法所编制的优化反分析计算程序，不仅能根据地质资料计算端承型单桩的荷载-沉降关系，而且可根据现场静荷载试验所得的荷载-沉降曲线反演分析桩周及桩端土层的岩土力学参数值，所得数据能真实反映单桩工作性态，为工程设计和计算提供理论依据。将该程序应用到工程实例中，取得了较为令人满意的结果。

STUDY ON ACTION MECHANISM OF END BEARING PILES AND ITS APPLICATION

The interaction mechanism of pile and soil for end bearing type piles is studied. A new ground-pile system model, which considers the complicity of the system and the influence of sound bearing stratum under the pile tip on stress and displacement of multilayer soil around the pile, is established by using generalized elastic theory method and mirror imagine method. A theory is given for design and calculation of end bearing pile foundation. The optimization back analysis program that employs this theory can be applied to not only the calculation of the load-settlement curves,but also the analysis of the values of geo-parameters of multilayer soil around and under piles. The method and the program are validated with engineering cases.